The present invention relates to apparatus for inspecting various articles, including containers, particularly of such a type lending itself to luggage and container inspection.
The recent high incidences of aircraft hijackings, theft, terrorist bombings, and other unlawful acts have prompted and necessitated the development of inspection systems for locating weapons, contraband, and other articles hidden in luggage so as to thwart such acts. Such systems generally have involved the use of x-rays but this leads to problems of shielding personnel and others from radiation. These problems also exist in various apparatus for inspecting various articles other than luggage.
Many prior art x-ray apparatus employed for inspecting various articles require the use of enclosing structures to prevent the escape of x-rays from the apparatus into the surrounding area and the consequent possibility of the irradiation of persons in this area by the escaping x-rays. Such enclosing structures can be x-ray impermeable hanging doors, telescoping doors, or other suitable, relatively rigid parts.
Another type of x-ray apparatus utilizes flexible curtains that are x-ray impermeable, one variety of such curtains being in the form of hanging strips of lead-containing flexible material.
By federal regulatory agency requirements, x-ray apparatus of the above type are required to have a certain minimum distance between the entry and exit ports of the machine and the x-ray beam, so as to avoid the possibility of a person inadvertently thrusting his arm or another part of his body into the x-ray beam.
To meet the federal safety requirements, the presently known versions of x-ray inspection apparatus provide for an outer envelope whose openings for inserting and removing the various inspected articles, are located such that they are at a minimum specified distance (presently 36 inches) from the fringes of the primary x-ray beam. Such an apparatus includes two tunnels located between the path of the x-ray beam and, respectively, the article entry and exit ports, such tunnels being completely closed on all sides, and a conveyor belt extending from the entry port, through the vicinity of the x-ray beam, to the exit port. Where the conveyor belt is co-extensive with the tunnels, the articles for inspection are required to be inserted into the tunnel, requiring some manipulation, so, to avoid this disadvantage, the apparatus is constructed so that the conveyor belt extends for considerable distances beyond the entry and exit ports. However, this type of structure is undesirable because of the resulting greater size and cost of the apparatus.
The present invention seeks to overcome this disadvantage and to provide other benefits as well.